Hi Gaylon,
Good to see that you are going for the Rotary Engine build, it will certainly make for a fantastic car. At the end of 2010 i had started putting together my own Rx8 build but decided that, commercially, it was no the way forward for Saturn. At the time i had concluded that the easiest way for the Roadster was to use standard Sierra uprights and suspension and just use the engine, gearbox, diff and loom from the Rx8. It was coming together quite nicely to.
There's a link below to a thread i started with Saturn's own build:
http://www.haynes.co.uk/forums/showthread.php?t=5208
Will be good to see yours as you go along. It's a big shame that the seats dont quite fit as they are great seats.
Andrew